Tape binding device

ABSTRACT

A tape binding device includes a loop forming mechanism for forming a loop for winding a material to be bound at an end of a tape. The loop forming mechanism includes a plurality of belt conveying mechanisms arranged in a polygonal shape in a conveyance direction for absorbing the tape by air suction and conveying the tape. Each of the belt conveying mechanisms includes a plurality of endless conveying belts extending parallel to the conveyance direction and arranged in a direction perpendicular to the conveyance direction with a space for air suction provided therebetween.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a tape binding device that binds amaterial to be bound using a tape.

2. Description of Related Arts

In recent years, tape binding devices that form rectangular loops oftapes by sucking in air through a large number of holes formed inconveying belts to absorb the tapes to the conveying belts and conveythe tapes are proposed (see, for example, WO95/019913).

However, in the tape binding device disclosed in WO95/019913, only onebelt is wound around a large number of pulleys so that the directionthereof is changed many times. Therefore, the only one belt circulatesthrough the whole of a very long path bent at the pulleys many times.Therefore, the tension of the only one belt is liable to be partiallyexcessive. As a result, an electric motor for driving the belt requiresa very large torque. Therefore, a large-sized electric motor must beused, and thus the size of the binding device is increased.

At the corners of the rectangular loops, the conveyance directions ofthe tapes must be changed at right angles thereto. In the tape bindingdevice disclosed in WO95/019913 using the only one belt, curved guideplates for direction change are provided at the corners of therectangular loop.

However, in the tape binding device disclosed in WO95/019913 using theonly one belt, the belt is wound around the respective outer sides ofthe pulleys. Therefore, the length of the fixed guide plate fordirection change is increased. Since an end of the tape slides relativeto the long fixed guide plate, the end of the tape that receives slidingresistance is easily prevented from being conveyed.

Particularly when a material to be bound is one containing water such astofu, for example, the tape may be absorbed to the long fixed guideplate by the water that has attached to the tape. Furthermore, when thetape is in a thin film shape, it may be electrostatically absorbed tothe long fixed guide plate. In these cases, the loop of the tape cannotbe satisfactorily formed.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a small-sized tapebinding device capable of satisfactorily forming a loop of a tape whenthe loop is formed by conveying the tape using air suction.

In order to attain the above-mentioned object, the present inventionincludes a loop forming mechanism for forming a loop for winding amaterial to be bound at an end of a tape. The loop forming mechanismincludes a plurality of belt conveying mechanisms arranged in apolygonal shape in a conveyance direction for absorbing the tape by airsuction and conveying the tape. Each of the belt conveying mechanismsincludes a plurality of endless conveying belts extending parallel tothe conveyance direction and arranged in a direction perpendicular tothe conveyance direction with a space for air suction providedtherebetween.

In the conventional case where only one elongate belt is bent many timesthrough a large number of pulleys, the tension of the longitudinal beltis partially excessive. On the other hand, in the present invention, theplurality of belt conveying mechanisms arranged in a polygonal shape areused. Therefore, the number of times of bending the belt can be madesignificantly reduced, as compared with the conventional case. As aresult, the tension of the belt can be significantly reduced. Therefore,a small-sized electric motor can be used as an electric motor fordriving the belt conveying mechanisms, and thus the tape binding devicecan be miniaturized.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic front view of a tape binding device according toan embodiment of the present invention;

FIG. 2 is a schematic perspective view of the tape binding device;

FIG. 3 is a schematic sectional view of an upper part of the tapebinding device;

FIG. 4 is a sectional view taken along a line IV-IV shown in FIG. 3.

FIG. 5 is a partially broken perspective view of a conveying belt;

FIG. 6 is a sectional view of the conveying belt and a second pulley;

FIG. 7 is a sectional view taken along a line VII-VII shown in FIG. 3;

FIG. 8A is a schematic view of a connection of a second belt conveyingmechanism and a third belt conveying mechanism, showing a stateimmediately before delivery of a tape from the second belt conveyingmechanism to the third belt conveying mechanism;

FIG. 8B is a schematic view of the connection of the second beltconveying mechanism and the third belt conveying mechanism, showing astate immediately after the delivery of the tape from the second beltconveying mechanism to the third belt conveying mechanism;

FIG. 9 is a schematic view showing a configuration of a conveying rollerand a conveying belt in a supplying mechanism and their surroundings;

FIG. 10 is a schematic view showing a configuration of the conveyingroller and the conveying belt in the supplying mechanism and theirsurroundings, showing a state where a tape T is conveyed with the tapesandwiched between the conveying roller and the conveying belt;

FIG. 11 is a partially broken side view of a cutting mechanism, aheating mechanism, and a claming mechanism and a driving mechanismincluding cams for respectively driving the mechanisms;

FIG. 12 is a schematic front view of the cutting mechanism, showing astate before cutting;

FIG. 13 is a schematic front view of the cutting mechanism, showing astate after cutting;

FIG. 14 is a schematic front view of the heating mechanism;

FIG. 15 is a schematic front view of the clamping mechanism;

FIG. 16A is a schematic view of a receiving plate and its drivingmechanism, showing a state where the receiving plate retreats from atape passage groove;

FIG. 16B is a schematic view of the receiving plate and its drivingmechanism, showing a state where the receiving plate advances into thetape passage groove;

FIG. 17 is a schematic view of a driving mechanism for a loop formingmechanism and the supplying mechanism;

FIG. 18A is a schematic view showing the step of the tape bindingdevice, showing a state where a loop of a tape is formed;

FIG. 18B is a schematic view showing the step of the tape bindingdevice, showing a state where an end of a tape having a loop formedtherein is sandwiched between a first clamp and the receiving plate;

FIG. 19A is a schematic view showing the step of the tape bindingdevice, showing a state where a loop is tightened around the peripheryof a material to be bound;

FIG. 19B is a schematic view showing the step of the tape bindingdevice, showing a state where an overlapped portion of a tape issandwiched between a second clamp and the receiving plate;

FIG. 19C is a schematic view showing the step of the tape bindingdevice, showing a state where a heater is pressed against an overlappedportion of a tape to heat and fuse the tape;

FIG. 20 is an exploded perspective view of a belt conveying mechanismand a fixed guide plate in another embodiment of the present invention;

FIG. 21 is a schematic sectional view of the belt conveying mechanismand the fixed guide plate shown in FIG. 20;

FIG. 22 is a partially broken perspective view of a conveying belt instill another embodiment of the present invention; and

FIG. 23 is a sectional view of the conveying belt shown in FIG. 22 and atape.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present invention will be described whilereferring to the attached drawings.

FIG. 1 is a schematic front view of a tape binding device 1 according toan embodiment of the present invention, and FIG. 2 is a schematicperspective view of the tape binding device 1. Referring to FIG. 1, thetape binding device 1 includes a device main body 2, and a table 3, onwhich a material to be bound A is to be placed, provided at the centerin the height direction of the device main body 2. As shown in FIG. 2, atape passage groove 4 through which a tape T for binding the material tobe bound A vertically passes is formed in the table 3. The table 3 has afront part 3 a and a rear part 3 b sandwiching the tape passage groove 4therebetween in the front and rear direction. Furthermore, there isprovided a peripheral wall 3 c extending downward from the table 3.

As shown in FIG. 1, a loop formation space 5 for forming a loop at anend of the tape T is provided above the table 3 in the device main body2. A loop forming mechanism 6 for forming a loop in the loop formationspace 5 includes a negative pressure groove formation frame 7 arrangedin a square annular shape, first to fourth belt conveying mechanisms 11to 14, and an air suction pump 8 that sucks air through the negativepressure groove formation frame 7 in order to absorb the tape T to aconveying belt in each of the belt conveying mechanisms 11 to 14.

Specifically, the negative pressure groove formation frame 7 has agroove shape in section to define a negative pressure groove 7 a, asshown in FIG. 4. The negative pressure groove formation frame 7 has alower frame 21, a vertical frame 22, an upper frame 23, and a verticalframe 24, as shown in FIGS. 1 and 2. The lower frame 21, the verticalframe 22, the upper frame 23, and the vertical frame 24 are arranged inthis order in a square annular shape. The lower frame 21 connects lowerends of a pair of the vertical frames 22 and 24, and the upper frame 23connects upper ends of the pair of vertical frames 22 and 24.

The pair of vertical frames 22 and 24 and the upper frame 23 arearranged above the table 3, and the lower frame 21 is arranged below thetable 3. As shown in FIGS. 1 and 3, the first belt conveying mechanism11 is accommodated within the lower frame 21, the second belt conveyingmechanism 12 is accommodated within the right vertical frame 22, thethird belt conveying mechanism 13 is accommodated within the upper frame23, and the fourth belt conveying mechanism 14 is accommodated withinthe left vertical frame 24.

Referring to FIG. 3, each of the belt conveying mechanisms 11 to 14includes a plurality of conveying belts 19 provided side by side. Theconveying belt 19 in the first belt conveying mechanism 11 is woundbetween a first pulley 41 and a second pulley 42. The conveying belt 19in the second belt conveying mechanism 12 is wound between the secondpulley 42 and a third pulley 43. The conveying belt 19 in the third beltconveying mechanism 13 is wound between the third pulley 43 and a fourthpulley 44. The conveying belt 19 in the fourth belt conveying mechanism14 is wound between the fourth pulley 44 and a fifth pulley 45.

Thus, the conveying belts 19 in the adjacent first and second beltconveying mechanisms 11 and 12 are wound around the common second pulley42. The conveying belts 19 in the adjacent second and third beltconveying mechanisms 12 and 13 are wound around the common third pulley43. Furthermore, the conveying belts 19 in the adjacent third and fourthbelt conveying mechanisms 13 and 14 are wound around the common fourthpulley 44. The first, second, third and fourth belt conveying mechanisms11 to 14 are arranged in a rectangular shape in a conveyance directionL1 extending in a counterclockwise direction in FIG. 3.

Referring to FIGS. 1 and 2, the tape binding device 1 includes asupplying mechanism 9 for supplying the tape T to the loop formingmechanism 6. The supplying mechanism 9 includes a tape roll 10 rotatablysupported by the device main body 2.

Referring to FIGS. 1 and 3, the supplying mechanism 9 includes aconveying roller 31 and a conveying belt 32, rotatable forward andbackward, which convey the tape T delivered from the tape roll 10 withthe tape T sandwiched therebetween in order to supply the tape T to theloop forming mechanism 6.

Referring to FIGS. 1 and 2, the supplying mechanism 9 includes anaccumulator mechanism 33 that is interposed between the tape roll 10 andthe conveying belt 32 and can pool the tape T having a predeterminedlength.

The accumulator mechanism 33 includes a plurality of rollers 34 and 37.The respective positions of the upper rollers 34 and 35 are fixed, whilethe lower rollers 36 and 37 are supported by the device main body 2 soas to be movable up and down. Specifically, a supporting shaft of eachof the rollers 36 and 37 is supported so as to be movable up and down bya guide groove 38 formed in the device main body 2. Furthermore, each ofthe rollers 36 and 37 is urged downward by an urging member (not shown)such as a weight or a spring, for example.

When the conveying roller 31 and the conveying belt 32 are rotatedforward (rotated in a clockwise direction in FIG. 1) and the tension ofthe tape T in the accumulator mechanism 33 is increased, the rollers 36and 37 respectively rise toward upper positions indicated by solid linesin FIG. 1 against the urging members. With the rise, the tape T pooledin the accumulator mechanism 33 is amply supplied to the loop formingmechanism 6.

On the other hand, when the conveying roller 31 and the conveying belt32 are rotated backward (rotated in a counterclockwise direction inFIG. 1) and the tension of the tape T in the accumulator mechanism 33 isdecreased, the rollers 36 and 37 respectively fall toward lowerpositions indicated by broken lines in FIG. 1 by the function of theurging members. With the fall, the tape T having a predetermined lengthis pooled in the accumulator mechanism 33.

Referring to FIG. 3, a first clamping mechanism and cutting mechanism15, a heating mechanism 16, and a second clamping mechanism 17 arearranged between the conveying roller 31 and a start end of the firstbelt conveying mechanism 11. Furthermore, there is provided a receivingplate 18, which advances into the tape passage groove 4 from the backside of paper (a position below the rear part 3 b of the table 3), andis arranged in a position above the first clamping mechanism and cuttingmechanism 15, the heating mechanism 16, and the second clampingmechanism 17.

A guiding member 25 that guides the tape T conveyed by the conveyingbelt 19 in the fourth belt conveying mechanism 14 to a position belowthe receiving plate 18 is arranged in the vicinity of the fifth pulley45 in the fourth belt conveying mechanism 14. A part of the guidingmember 25 is formed in a comb shape so as to enter an area between theadjacent conveying belts 19 in the fourth belt conveying mechanism 14.

As shown in FIG. 4, the conveying belts 19 in the third belt conveyingmechanism 13 are arranged with a space S for air suction providedtherebetween. The other belt conveying mechanisms 11, 12, and 14 alsohave the same configuration, which is not illustrated.

As shown in FIGS. 5 and 6, the conveying belt 19 has a tape conveyingsurface 19 a composed of its outer peripheral surface and a pulleyengagement surface 19 b composed of its inner peripheral surface. Teeth20 extending in a width direction W1 perpendicular to the conveyancedirection L1 of the conveying belt 19 are formed on the pulleyengagement surface 19 b. That is, the conveying belt 19 is composed of atoothed belt (cogged belt) having the teeth 20 provided on the pulleyengagement surface 19 b. Furthermore, each of the pulleys 41 to 45 iscomposed of a toothed pulley (only the second pulley 42 is illustratedin FIG. 6).

Referring to FIG. 7, the plurality of conveying belts 19 in the secondbelt conveying mechanism 12 and the plurality of conveying belts 19 inthe third belt conveying mechanism 13 are wound around the common thirdpulley 43. A supporting shaft 43 a of the third pulley 43 is rotatablysupported on the negative pressure groove forming frame 7.

In an axial direction X1 of the third pulley 43, the plurality ofconveying belts 19 in the second belt conveying mechanism 12 and theplurality of conveying belts 19 in the third belt conveying mechanism 13are alternately wound with the conveying belt or belts interposedbetween the other conveying belt or belts (with one conveying beltinterposed between the other conveying belts in an example shown in FIG.7).

Furthermore, the conveying belts 19 in each of the belt conveyingmechanisms 12 and 13 are symmetrical with respect to a center positionTW1 in a width direction TW of the tape T perpendicular to theconveyance direction L1 of the tape T. Similarly, the conveying belts 19in each of the other belt conveying mechanisms 11 and 14 are symmetricalwith respect to the center position TW1 in the width direction TW.

Assuming that the conveying belts 19 in the belt conveying mechanism 12and the conveying belts 19 in the belt conveying mechanism 13 arealternately arranged, for example, when the number of conveying belts 19in the second belt conveying mechanism 12 is four, the number ofconveying belts 19 in the third belt conveying mechanism 13 is three,and the conveying belt 19 at the center out of the three conveying belts19 is arranged along the center TW1 in the width direction TW of thetape T, as shown in FIG. 7.

For example, each of the second belt conveying mechanism 12 and thethird belt conveying mechanism 13 may be composed of two conveying belts19, and the two conveying belts 19 in the third belt conveying mechanism13 may be arranged between the two conveying belts 19 in the second beltconveying mechanism 12.

Since the plurality of conveying belts 19 in each of the belt conveyingmechanisms 12 and 13 are symmetrical with respect to the center positionTW in the width direction TW of the tape T, as shown in FIG. 7, theconveying belts 19 in the second belt conveying mechanism 12 can berespectively arranged at a pair of ends TW2 in the width direction TW ofthe tape T. However, the conveying belts 19 in the third belt conveyingmechanism 13 are forced to be respectively arranged at positionsslightly spaced apart from the pair of ends TW2 in the width directionTW of the tape T. Therefore, the distance from a front wall 23 a or arear wall 23 b of the upper frame 23 to the conveying belt 19 is long.

Therefore, it is preferable that the ends TW2 in the width direction TWof the tape T are respectively guided in the conveyance direction L1 (adirection perpendicular to the paper surface, which is not illustratedin FIG. 4) using guide plates 39 serving as guiding members fixed in anorthogonal manner to inner wall surfaces of the front wall 23 a and therear wall 23 b and extending in the conveyance direction L1, as shown inFIG. 4, in order to prevent unnecessary deflection of the tape T.

Furthermore, a plurality of annular plates 26 serving as guiding membershaving a larger diameter than that of the third pulley 43 are providedon an outer peripheral surface 43 b of the third pulley 43 so as to berotatable together with the third pulley 43. The annular plate 26 isarranged between the conveying belt 19 in the second belt conveyingmechanism 12 and the conveying belt 19 in the third belt conveyingmechanism 13 which are adjacent to each other.

Referring to FIG. 3, the annular plate 26 serving as the guiding memberthat rotates together with the common second pulley 42 around which theconveying belts 19 in the first and second belt conveying mechanisms 11and 12, which are adjacent to each other, are wound is arrangedcoaxially with the second pulley 42. The annular plate 26 serving as theguiding member that rotates together with the common third pulley 43around which the conveying belts 19 in the second and third beltconveying mechanisms 12 and 13, which are adjacent to each other, arewound is arranged coaxially with the third pulley 43. Furthermore, theannular plate 26 serving as the guiding member that rotates togetherwith the common fourth pulley 44 around which the conveying belts 19 inthe third and fourth belt conveying mechanisms 13 and 14, which areadjacent to each other, are-wound is arranged coaxially with the fourthpulley 44.

As shown in FIG. 8A, the end Ta of the tape T that has been conveyed bythe conveying belt 19 in the second belt conveying mechanism 12 isstripped from the conveying belt 19 in the second belt conveyingmechanism 12 by an outer periphery 26 a of the annular plate 26, havinga larger diameter than that of the third pulley 43, which rotatestogether with the third pulley 43 coaxially with the third pulley 43,and is delivered to the conveying belt 19 in the third belt conveyingmechanism 13, as shown in FIG. 8B, after the route thereof is changed.The annular plates 26 respectively provided in the second pulley 42 andthe fourth pulley 44 also perform the same function.

An annular member for changing the direction of the tape T is notlimited to the annular plate 26. For example, it may be an annular blockmember. One made of a metal or resin, for example, is usable as theannular member. Furthermore, an elastic member such as rubber may beused as the annular member. When the elastic member is used, the elasticmembers can be easily mounted on the pulleys 42 to 44. Furthermore, ageneral-purpose O ring can be also used. In this case, the manufacturingcost can be made low.

Referring to FIGS. 9 and 10, the conveying belt 32 is composed of anendless belt wound around a first pulley 51, a second pulley 52, and atensioner pulley 53. The conveying belt 32 includes a region stretchedbetween the first pulley 51 and the second pulley 52, and the regionincludes a region D1 in a curved shape along a predetermined region C1on a peripheral surface 31 a of the conveying roller 31.

It is preferable that a central angle E1 corresponding to thepredetermined region C1 on the peripheral surface 31 a of the conveyingroller 31 is in a range of 45 to 150 degrees. The central angle E1 ismore preferably in a range of 90 to 120 degrees and more preferably in arange of 105 to 115 degrees.

Since the conveying belt 32 is pressed against the peripheral surface 31a of the conveying roller 31 by the tension of the conveying belt 32itself, the peripheral surface 31 a of the conveying roller 31 can beuniformly pressed.

The tensioner pulley 53 serves to apply a tension to the conveying belt32. Specifically, the tensioner pulley 53 is rotatably supported aroundits supporting shaft 56 by a supporting member 55 rotatably supportedaround a support 54 by the device main body 2. The tensioner pulley 53is arranged at a position spaced a predetermined distance apart from thesupport 54.

The supporting member 55 is urged in the rotating direction by a tensioncoil spring 57, for example, as an urging member. As a result, thetensioner pulley 53 is urged in such a direction as to apply a tensionto the conveying belt 32. The tension coil spring 57 is interposedbetween a shaft 58, for example, as an engagement portion provided inthe device main body 2 and a shaft 59, for example, as an engagementportion provided in the supporting member 55. A tensioner mechanism 60is composed of the tensioner pulley 53, the supporting member 55 and thetension coil spring 57.

Furthermore, a plane P1 including a central axis 51 a of the firstpulley 51 and a central axis 52 a of the second pulley 52 crosses theconveying roller 31. By thus setting a positional relationship betweenthe first and second pulleys 51 and 52 that support the conveying belt32 and the conveying roller 31, a configuration in which the conveyingbelt 32 is provided with the region D1 in a curved shape and aconfiguration in which the conveying belt 32 is pressed against theperipheral surface 31 a of the conveying roller 31 by the tension of theconveying belt 32 itself can be easily realized.

Since the conveying belt 32 includes the region D1 in the curved shapealong the peripheral surface 31 a of the conveying roller 31, as shownin FIG. 10, the contact area of the conveying belt 32 and the conveyingroller 31 with the tape T in the conveyance direction L1 of the tape Tcan be large.

Even if a pressing force against the wide tape T requiring a conveyingforce is not strengthened, therefore, the tape T can be satisfactorilyconveyed without slipping with the tape T reliably sandwiched betweenthe conveying roller 31 and the conveying belt 32. The pressing forceagainst the tape T need not be strengthened, which can prevent the tapeT from being damaged. Furthermore, degradation such as wear does noteasily occur in the conveying roller 31 and the conveying belt 32, whichallows durability to be improved.

Particularly, the tensioner pulley 53 can apply a tension to theconveying belt 32. Even if the conveying belt 32 extends with time,therefore, the extension can be absorbed. Therefore, the pressing forceof the conveying belt 32 can be stably maintained for a long timeperiod, which allows a stable conveying force to be ensured.

Referring to FIG. 11, the first clamping mechanism and cutting mechanism15, the heating mechanism 16, and the second clamping mechanism 17 arerespectively driven so as to be movable up and down by first, second,and third cams 61, 62, and 63 that rotate together with a rotating shaft28 of an electric motor 27 as a driving member.

Referring to FIG. 12, the first clamping mechanism and cutting mechanism15 includes a support 65 supported so as to be movable up and down by apair of guides 64 fixed to the device main body 2, a cam follower 66supported so as to be rotatable on a lower part of the support 65 andmoving up and down together with the support 65, an urging member 67composed of a tension coil spring, for example, for urging the support65 downward, a first clamp 68 supported by the support 65 so as to bemovable up and down and capable of sandwiching the tape T between thefirst clamp 68 and a lower surface of the receiving plate 18, a cuttersupporting member 69 supported by the support 65 so as to be movable upand down, and a cutter 70 fixed on an upper part of the cuttersupporting member 69 for cutting the tape T by entering a cutter entrygroove 68 b (also see FIG. 11) formed on a lower surface 68 a of thefirst clamp 68.

A shaft 71 that moves together with the first clamp 68 penetrates thesupport 65. A large diameter portion 72 provided in the shaft 71 isurged upward by an urging member 73 composed of a compression coilspring fitted in the shaft 71, for example, so that the first clamp 68is urged toward its upper position. A stopper 74 that prevents the shaft71 from slipping off the support 65 is provided at a lower end of theshaft 71.

A shaft 75 that moves together with the cutter supporting member 69penetrates the support 65. A large diameter portion 76 provided in theshaft 75 is urged upward by an urging member 77 composed of acompression coil spring fitted in the shaft 75, for example, so that thecutter supporting member 69 is urged toward its upper position. Astopper 78 that prevents the shaft 75 from slipping off the support 65is provided at a lower end of the shaft 75.

The pushup by the cam 61 causes the support 65, the cutter supportingmember 69, and the first clamp 68 to rise together against the urgingmember 67, so that the tape T is first sandwiched between the firstclamp 68 and the lower surface of the receiving plate 18. This causesthe first clamp 68 to be positioned at its raised position by thereceiving plate 18, to regulate the upward movement of the first clamp68. A regulating member 30 receives a front end 18 a of the receivingplate 18, to regulate the upward movement thereof.

Thereafter, the further pushup by the cam 61 causes the support 65 andthe cutter supporting member 69 to rise, so that the tape T insertedthrough a tape insertion hole 79 formed between the cutter 70 on anupper surface of the cutter supporting member 69 and the lower surface68 a of the first clamp 68 is pressed into the cutter entry groove 68 bon the lower surface 68 a of the first clamp 68 by the cutter 70, asshown in FIG. 12, and is cut, as shown in FIG. 13.

Referring to FIG. 14, the heating mechanism 16 includes a support 81 ina T shape supported so as to be movable up and down by a pair of guides80 fixed to the device main body 2, a cam follower 82 supported so as tobe rotatable on a lower part of the support 81 and moving up and downtogether with the support 81, an urging member 83 composed of a tensioncoil spring, for example, for urging the support 81 downward, a heater84 composed of a planar heater, for example, provided on at least anupper surface 81 b of a heater support 81 a in an upper part of thesupport 81, and an electric wire 85 for feeding power to the heater 84.

The pushup by the cam 62 causes the support 81 and the heater 84 to risetogether against the urging member 83. An overlapped portion of the tapeT is pressed against the lower surface of the receiving plate 18 and isheated by the heater 84. As a result, the overlapped portion of the tapeT is thermally welded.

Referring to FIG. 15, the second clamping mechanism 17 includes asupport 87 supported so as to be movable up and down by a pair of guides86 fixed to the device main body 2, a cam follower 88 supported so as tobe rotatable on a lower part of the support 87 and moving up and downtogether with the support 87, an urging member 89 composed of a tensioncoil spring, for example, for urging the support 87 downward, and asecond clamp 90 in a horizontally long stick shape fixed on an upperpart of the support 87 and abuttable against the lower surface of thereceiving plate 18.

The pushup by the cam 63 causes the support 87 and the heater 84 to risetogether against the urging member 89, so that the end Ta of the tape Tis sandwiched between the second clamp 90 and the lower surface of thereceiving plate 18.

Referring to FIG. 16A, the receiving plate 18 extends forward andbackward, and is driven forward and backward by a driving mechanism 91.The driving mechanism 91 includes a guide shaft 93 having its end fixedto a supporting block 92 fixed to the device main body 2 and extendingforward and backward. A rear end 18 b of the receiving plate 18 is fixedto a movable body 94 supported by the guide shaft 93 so as to be movablein the axial direction of the guide shaft 93. The movable body 94 has aninsertion hole 94 a through which the guide shaft 93 is inserted so asto be relatively slidable. A stopper 101 that prevents the movable body94 from slipping off the guide shaft 93 is provided at a rear end of theguide shaft 93.

Furthermore, the supporting block 92 has a receiving plate insertiongroove 95 that supports the receiving plate 18 so that the receivingplate 18 is slidably movable forward and backward. The front end 18 a ofthe receiving plate 18 advances forward through the receiving plateinsertion groove 95.

The driving mechanism 91 includes an electric motor 96 as a drivingmember supported by the device main body 2, a rotating member 97 thatrotates together with a rotating shaft 96 a of the electric motor 96,and a connecting arm 96 that connects the rotating member 97 and themovable body 94 to each other. The connecting arm 98 has its one end 98a connected to the movable body 94 through a pivot 99 so as to berotatable and has the other end 98 b connected to the rotating member 97through a pivot 100 so as to be turnable. The pivot 100 is arranged inthe rotating member 97 at a position spaced a predetermined distanceapart from the rotating shaft 96 a of the electric motor 96.

A crank mechanism using the rotating member 97 and the connecting arm 98converts rotational motion of the electric motor 96 into linear motionof the receiving plate 18, to keep the forward and backward movementamounts of the receiving plate 18 large so that they can cope with acase where the wide tape T is used.

The receiving plate 18 moves between an advance position in which itadvances to the tape passage groove 4 in order to receive the materialto be bound A, as shown in FIG. 16B, and a retreat position in which itretreats from the tape passage groove 4, as shown in FIG. 16A.

Then, the tape binding operation of the tape binding device 1 will bedescribed. First, the conveying roller 31 and the conveying belt 32 inthe supplying mechanism 9 rotate forward, to supply the tape T to theloop forming mechanism 6. With the supply, the air suction pump 8 isdriven, so that negative pressure is generated within each of the frames21 to 24 in the negative pressure groove formation frame 7. Theconveying roller 31 in the supplying mechanism 9, the first pulley 41 inthe first belt conveying mechanism 11, and the fifth pulley 45 in thefourth belt conveying mechanism 14 are driven by the same drivingmechanism 110.

Specifically, as shown in FIG. 17, there are provided a pulley 111together rotatable coaxially with the conveying roller 31, a pulley 112together rotatable coaxially with the first pulley 41 in the first beltconveying mechanism 11, and a pulley 113 together rotatable coaxiallywith the fifth pulley 45 in the fourth belt conveying mechanism 14, anda common endless belt 114 is wound around the pulleys 111, 112, and 113.

A belt 118 is wound between a driving pulley 116 that is driven by anelectric motor 115 as a driving member and a pulley 117 that rotatestogether with the pulley 111. The pulley 111 is driven through the belt118 by the electric motor 115. With the driving, the pulleys 112 and 113are driven through the belt 114.

The pulley 111 is driven, so that the conveying roller 31 in thesupplying mechanism 9 is driven. Furthermore, the conveying belt 32 isdriven following the conveying roller 31. The pulleys 112 and 113 aredriven, so that the first pulley 41 in the first belt conveyingmechanism 11 and the fifth pulley 45 in the fourth belt conveyingmechanism 14 are driven. That is, the first pulley 41 serving as apulley at a start end of each of the belt conveying mechanisms 11 to 14and the fifth pulley 45 serving as a pulley at a final end thereof aredriven. This causes the whole of the belt conveying mechanisms 11 to 14to be driven.

Thus, the end Ta of the tape T is successively conveyed to the firstbelt conveying mechanism 11, the second belt conveying mechanism 12, thethird belt conveying mechanism 13, and the fourth belt conveyingmechanism 14, to form a loop TL of the tape T, as shown in FIG. 18A.

Then, the end Ta of the tape T is sandwiched between the raised firstclamp 68 in the first clamping mechanism and cutting mechanism 15 andthe receiving plate 18, as shown in FIG. 18B.

Then, the material to be bound A is placed on the receiving plate 18, asshown in FIG. 19A.

Then, the driving of the air suction pump 8 is stopped, so thatabsorption of the conveying belt 19 in each of the belt conveyingmechanisms 11 to 14 is released, and the conveying roller 31 and theconveying belt 32 are rotated backward, so that the loop TL istightened. Therefore, the tape T has a shape along the periphery of thematerial to be bound A.

Then, the overlapped portion Tb of the tape T is sandwiched between theraised second clamp 90 in the second clamping mechanism 17 and the lowersurface of the receiving plate 18, as shown in FIG. 19B. Then, theraised heater 84 in the heating mechanism 16 heats the overlappedportion Tb of the tape T with the overlapped portion Tb pressed againstthe lower surface of the receiving plate 18, to thermally weld theoverlapped portion Tb of the tape T, as shown in FIG. 19C.

The raised cutter 70 in the first clamping mechanism and cuttingmechanism 15 cuts an extra length portion of the tape T to complete thebinding at substantially the same timing as or slightly delayed timingfrom the operation of the heater 84, which is not illustrated.

According to the present embodiment, the following function and effectare produced. That is, in the conventional case where only one elongatebelt is bent many times through a large number of pulleys, the tensionof the longitudinal belt is partially excessive. On the other hand, inthe present embodiment, the plurality of belt conveying mechanisms 11 to14 arranged in a polygonal shape are used. Therefore, the number oftimes of bending of the conveying belt 19 can be reduced significantly,as compared with the conventional case. As a result, the tension of theconveying belt 19 can be significantly reduced. Therefore, a small-sizedmotor can be used as the electric motor 115 for driving the beltconveying mechanisms 11 to 14, and thus the tape binding device 1 can beminiaturized.

Since the conveying belts 19 in the adjacent first and second beltconveying mechanisms 11 and 12 are wound around the common second pulley42, the distance between the tape conveying surfaces 19 a of theconveying belts 19 can be brought closer to each other between the firstand second belt conveying mechanisms 11 and 12. Therefore, it ispossible to satisfactorily change the direction of the tape T in thevicinity of the second pulley 42.

Since the conveying belts 19 in the adjacent second and third beltconveying mechanisms 12 and 13 are wound around the common third pulley43, and the conveying belts 19 in the adjacent third and fourth beltconveying mechanisms 13 and 14 are wound around the common fourth pulley44, the same effect is obtained.

The annular plate 26 that rotates together with the common second pulley42 around which the conveying belts 19 in the adjacent first and secondbelt conveying mechanisms 11 and 12 are wound is arranged coaxially withthe second pulley 42. The annular plate 26 that rotates together withthe common third pulley 43 around which the conveying belts 19 in theadjacent second and third belt conveying mechanisms 12 and 13 are woundis arranged coaxially with the third pulley 43. Furthermore, the annularplate 26 that rotates together with the common fourth pulley 44 aroundwhich the conveying belts 19 in the adjacent third and fourth beltconveying mechanisms 13 and 14 are wound is arranged coaxially with thefourth pulley 44.

As shown in FIGS. 8A and 8B, for example, the annular plate 26 arrangedcoaxially with the common third pulley 43 around which the conveyingbelts 19 in the adjacent second and third belt conveying mechanisms 12and 13 are wound rotates together with the third pulley 43. When theannular plate 26 changes the direction of the tape T, therefore, arelative speed between the outer periphery 26 a of the annular plate 26and the tape T is low. As a result, the annular plate 26 does not imposeon the tape T such sliding resistance as to prevent the tape T frombeing conveyed.

Even if the tape T is absorbed to the outer periphery 26 a of theannular plate 26 by water that has adhered to the tape T when thematerial to be bound A containing water such as tofe, for example, isbound, the tape T can be satisfactorily conveyed toward the next thirdbelt conveying mechanism 13 because the annular plate 26 rotatestogether with the third pulley 43. This is also effective when a thintape T is electrostatically absorbed to a peripheral surface of theannular plate 26.

When the tape T is absorbed to the conveying belt 19 by suction and isconveyed to form the rectangular loop TL, therefore, the loop TL of thetape T can be satisfactorily formed. Thus, the loop TL can be alsosatisfactorily formed when the material to be bound A including watersuch as tofu is bound and when the material to be bound A is bound usingthe tape T that is easy to be electrostatically absorbed. Furthermore,the annular plate 26 may be only disposed in each of the pulleys 42, 43,and 44. Therefore, the configuration is simple.

The plurality of conveying belts 19 in each of the second and third beltconveying mechanisms 12 and 13 are symmetrical with respect to thecenter position TW1 in the width direction TW of the tape Tperpendicular to the conveyance direction L1 of the tape T. Therefore,the tape T can be absorbed to the conveying belts 19 in each of the beltconveying mechanisms 11 to 13 uniformly, and can be satisfactorilyconveyed. The same is true for the other belt conveying mechanisms 11and 14.

Since the conveying belts 19 in the second belt conveying mechanism 12and the conveying belts 19 in the third belt conveying mechanism 13 arealternately arranged in the axial direction X1 of the third pulley 43,and the annular plates 26 are respectively arranged between theconveying belts 19 in the second belt conveying mechanism 12 and theconveying belts 19 in the third belt conveying mechanism 13, thedirection of the wide tape T can be satisfactorily changed. The same istrue for the respective annular plates 26 coaxial with the second pulley42 and the fourth pulley 44.

The annular plate 26 may be formed of a single material integrally witheach of the pulleys 42, 43, and 44. Alternatively, the annular plate 26composed of another member may be attached to each of the pulleys 42,43, and 44.

Since the conveying belts 19 in the belt conveying mechanisms 11 to 14are respectively composed of toothed belts wound around the pulleys 42,43, and 44 composed of toothed pulleys. Therefore, the conveying belt 19is not shifted from the toothed pulley. Therefore, no excessive tensionis applied to the conveying belt 19. From this point, a small-sizedelectric motor-can be also used as the electric motor 115 for drivingthe belt conveying mechanisms 11 to 14, and thus the tape binding device1 can be miniaturized.

The present invention is not limited to the above-mentioned embodiment.Although in the present embodiment, the annular plate 26 that rotatestogether with the third pulley 43 is used as a guiding member forforcing the direction of the tape T to be changed from the second beltconveying mechanism 12 to the third belt conveying mechanism 13, whichare adjacent to each other in the conveyance direction L1, the annularplate 26 may be replaced with a fixed guide plate 260 as shown in FIG.20.

The fixed guide plate 260 as a guiding member includes a main body 261and a plurality of guiding pieces 262. The main body 261 is opposed tothe outer periphery of the third pulley 43 fixed to the negativepressure groove formation frame 7 and serving as a common pulley. Theguiding piece 262 extends into the space S between the conveying belts19 from the main body 261. The guiding piece 262 has an inclined guidingsurface 262 that is inclined in the conveyance direction L1 of the tapeT and is abuttable to the end Ta in the conveyance direction L1 of thetape T.

While the fixed guide plate 260 is used as a guiding member in thepresent embodiment, the guiding piece 262 in the fixed guide plate 260enters the space S between the conveying belts 19 in an inclined manner,as shown in FIG. 21. Therefore, the end Ta of the tape T conveyed by theconveying belt 19 does not collide with an end surface of the guidingpiece 262. That is, the end Ta of the tape T is smoothly stripped fromthe conveying belt 19 in the second belt conveying mechanism 12 by theinclined guiding surface 263 of the guiding piece 262, and issatisfactorily delivered to the conveying belt 19 in the third beltconveying mechanism 13.

Furthermore, a groove 29 extending in the width direction W1perpendicular to the conveyance direction L1 of the conveying belt 19may be formed on the tape conveying surface 19 a of the conveying belt19, as shown in FIG. 22.

In this case, air can be sucked in through a large number of grooves 29on the tape conveying surface 19 a, which can improve the capability ofthe conveying belt 19 to convey the tape T. Particularly, the tape T canbe absorbed over the whole area in the width direction W1 of theconveying belt 19. Moreover, the tape T in a small amount enters thegroove 29 in a convex manner, as shown in FIG. 23. Therefore, thecapability of the conveying belt 19 to convey the tape T can beenhanced, which allows the tape T to be satisfactorily conveyed withoutslipping. Note that the groove 29 may be inserted through at least oneof the pair of spaces S with the conveying belt 19 held therebetween.

While the present invention has been described in detail by a specificembodiment, those skilled in the art that have understood theabove-mentioned contents will consider their alteration, modificationand equivalents. Therefore, the present invention should be in the scopeof claims and its equivalents.

This application is based on and claims the benefit of priority fromJapanese Patent Application No. 2007-340919 filed with the JapanesePatent Office on Dec. 28, 2007 and Japanese Patent Application No.2008-075883 filed with the Japanese Patent Office on Mar. 24, 2008, thecontents of which are incorporated herein by reference.

1. A tape binding device, comprising: a loop forming mechanism forforming a loop for winding a material to be bound at an end of a tape,wherein the loop forming mechanism includes a plurality of beltconveying mechanisms arranged in a polygonal shape in a conveyancedirection for absorbing the tape by air suction and conveying the tape,and each of the belt conveying mechanisms includes a plurality ofendless conveying belts extending parallel to the conveyance directionand arranged in a direction perpendicular to the conveyance directionwith a space for air suction provided therebetween.
 2. The tape bindingdevice according to claim 1, wherein the plurality of belt conveyingmechanisms include belt conveying mechanisms that are adjacent to oneanother in the conveyance direction, and the respective conveying beltsin the belt conveying mechanisms that are adjacent to each other in theconveyance direction are wound around a common pulley.
 3. The tapebinding device according to claim 2, further comprising a guiding memberfor forcing a direction of the tape to be changed from one of the beltconveying mechanisms that are adjacent to each other in the conveyancedirection to the other belt conveying mechanism.
 4. The tape bindingdevice according to claim 3, wherein the guiding member includes anannular member provided so as to be rotatable together and coaxial withthe pulley and having a larger diameter than that of the pulley, and thedirection of the tape is forced to be changed from one of the beltconveying mechanisms that are adjacent to each other in the conveyancedirection to the other belt conveying mechanism by an outer periphery ofthe annular member.
 5. The tape binding device according to claim 4,wherein the annular member includes an annular plate.
 6. The tapebinding device according to claim 3, wherein the annular member includesan annular elastic member.
 7. The tape binding device according to claim3, wherein the loop forming mechanism includes a negative pressuregroove formation frame forming a negative pressure groove communicatingwith the space, the guiding member includes a main body fixed to thenegative pressure groove formation frame and opposed to an outerperiphery of the common pulley, and a guiding piece extending into thespace from the main body, and the guiding piece has an inclined guidingsurface that is inclined in the conveyance direction and is abuttable tothe end in the conveyance direction of the tape.
 8. The tape bindingdevice according to claim 1, wherein the conveying belts in each of thebelt conveying mechanisms that are adjacent to each other in theconveyance direction are symmetrical with respect to a center positionin a width direction of the tape perpendicular to the conveyancedirection.
 9. The tape binding device according to claim 1, wherein theconveying belt in each of the belt conveying mechanism is composed of atoothed belt wound around a toothed pulley.
 10. The tape binding deviceaccording to claim 1, wherein the plurality of conveying belts in eachof the belt conveying mechanisms include a conveying belt having a tapeconveying surface having a large number of grooves to be communicatedwith the space formed therein.